historic vessels as part of the creation of a comprehensive national inventory of those vessels. That meant extensive travel throughout the United States, visiting ships, sailing, steaming and motoring on them, inspecting them during shipyard haulouts and repairs, climbing masts, crawling through engine rooms, and not just conducting a desk-top survey from afar. The first inventory of the large historic ships in the United States, led by Delgado, was completed and published in 1990 in conjunction with J. Candace Clifford. It remains the basis for the National Park Service's ongoing, now digital inventory. Working from the inventory, Delgado applied the criterion of the National Register of Historic Places and the National Historic Landmarks Program to determine which of some 330 large historic vessels were of national significance. He led the resulting effort, which studied study 142 ships for designation as national landmarks. He personally prepared the studies for 54 properties, including several lightships, fireboats, tugboats, submarines, and other warships. Delgado's work led to the largest group of maritime resources being designated as National Historic Landmarks since the creation of the NHL Program. Among the ships and sites he personally studied and nominated are the schooner Adventuress, USS Albacore, the fireboat Firefighter, the schooner Governor Stone, the U.S. Navy tug USS Hoga, the aircraft carriers USS Lexington and USS Hornet, schooner American Eagle, the tugboat Arthur Foss, the fireboat Duwamish, the destroyer USS Edson, the Victory Ship Lane Victory, the Ambrose Lightship, the river steamboat Nenana, the four-masted ship Falls of Clyde, the schooner Bowdoin, the bark Elissa the nuclear ship Savannah, and the excursion steamer Virginia V. Delgado also conducted the NHL study for Lowell's Boat Shop in Amesbury, Massachusetts, as well as the home of former First Lady Lou Henry Hoover at Stanford University. As part of his duties, and with his degree in maritime archaeology, Delgado closely interacted with the National Park Service's Submerged Cultural Resources Center as well as the Chief Archaeologist of the NPS during his tenure with the National Maritime Initiative. This included co-authoring the guidelines for the implementation of the Abandoned Shipwreck Act of 1987 following a series of national public meetings, several of which Delgado personally led. Delgado also joined the SCRU in their fieldwork in various parks, including his former assignment, Golden Gate National Recreation Area, Cape Cod National Seashore, Fort Jefferson National Monument (now a National Park, the USS Arizona Memorial,